Fate favors some films. A stalled elevator threw together noted film restorer Serge Bromberg and Inès Clouzot, widow of director Henri-Georges Clouzot. In the course of two stranded hours, a discussion of Clouzot’s unfinished film, Inferno, inevitably arose. Subsequently, Inés Clouzot agreed to give Bromberg access to the surviving 13 hours of film. This stunning footage becomes the backbone of the resulting documentary, which offers a fascinating, partial reconstruction of Inferno while chronicling the production’s disintegration. The year was 1964. Clouzot, maker of suspense thrillers Diabolique and The Wages of Fear, had written the story of a jealous husband and his mental breakdown. He’d assembled an extraordinary cast and crew, including Serge Reggiani and Romy Schneider as his leads. After seeing rushes of his innovative visual experiments with lighting, lenses and makeup, his financial backers had given him an unlimited budget. What went wrong? In interviews with surviving cast and crew a few clues emerge. For a meticulous, detail-obsessed filmmaker like Clouzot, the unlimited budget was a curse as much as a boon. The insomniac director drove his cast and crew to the point of exhaustion, particularly lead actor Reggiani. Most crucially, the director’s grandiose ambitions sabotaged the film. Production slowed to a crawl as Clouzot lost himself in Op Art abstractions and psychedelic visuals that anticipate later films. Would the film have been the masterpiece he intended? It’s a question that will remain forever unanswered. The documentary does a superb job of tantalizing us with what might have been.